1. Field of the Invention
The present invention relates generally to skimmer systems for removing quantities of oil that is present on or near the surface of a body of water. More particularly, the present invention concerns an oil skimmer device having a primary weir that is selectively positioned relative to the surface of a body of water by means of a plurality of float members that are each adjustably mounted to the skimmer device. Even more specifically the present invention concerns the use of a secondary weir located within and below the level of the primary weir to ensure efficiency of oil recovery and to minimize the volume of water that enters the skimmer during skimming activity
2. Description of the Prior Art
Apparatus for skimming spilled oil from the surface of water have been used for a good number of years. In most cases, oil skimmers take the form of large or small boats that are fitted with a weir device, with the position of the weir being controlled by a crane and hoist mechanism. Typically buoyant booms are positioned downwind or down current on the water and serve to collect and retain oil so that it can be recovered by skimmer boats. In some cases the skimmer boats are provided with an endless oil attracting belt that separates oil from the surface of a body of water and employs rolls to squeeze the collected oil from the endless belt and deposit it in one or more skimmer chambers of the vessel.
It is known that spilled crude oil will often collect other contaminants and form a jelled oil/water/contaminant mixture that is difficult to recover by skimming and is difficult to pump when its recovery is accomplished. This jelled substance often extends well below the surface of the water, so that conventional skimmer devices have difficulty recovering it and handling it when the substance is recovered.
While oil skimmer devices are often satisfactory for recovery of spilled oil from rivers, streams and other bodies of water, when spilled oil moves to quite shallow water such as marshes, near beaches, shallow bays and the like most oil skimmer mechanisms cannot access such shallow water. Accordingly, when major oil spills occur and large quantities of oil are released, especially for long periods of time, it is practically impossible to prevent the spilled oil from causing significant environmental damage to marshes and other sensitive regions near shore. There is a long felt need for apparatus and systems that can accomplish effective recovery of spilled oil in both deep and shallow water conditions. It is desirable therefore to provide an oil skimmer mechanism that can be used in deep water conditions and can also be used in shallow water conditions and can be effectively used with or without booms for oil collection.